The effect of surface pretreatment with H₃PO₄ and NaOCl on dentin and the adhesive mechanism were investigated. Although shear bond strength decreased after application of thermal stress in both cases of ground dentin and dentin pretreated with H₃PO₄ alone, there was no decrease in shear bond strength when dentin was pretreated with H₃PO₄ and NaOCl even after thermal stress was applied 50, 000 times. According to ESCA analysis, and SEM and' TEM observations, dentin pretreated with H₃PO₄ and NaOCl appeared to remain intact. The surface was also free of collagen denatured by H₃PO₄ treatment and appeared smoother with opened tubules and a rough construction. A hybrid layer which is contained resin-encapsulated hydroxylapatite was created in relatively intact dentin.

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The purpose of this study was to investigate the degree of marginal leakage in cast restorations luted with various cements . The marginal leakage of adhesive resins was compared with that of conventional luting materials (zinc phosphate cement and glass-ionomer cement) according to dye penetration tests and artificial secondary caries resistance in vitro. The shear bond strength of four luting materials to the dentin was also measured.
The results were as follows:
1) The shear bond strength of adhesive resins to dentin was clearly greater than that of zinc phosphate cement and glass-ionomer cement.
2) The degree of dye penetration in the case of adhesive resins showing high bond strength to dentin, was less than that of conventional luting materials.
3) The characteristic shapes of artificial secondary caries when cast restorations were luted with four different cements were obtained.
Artificial secondary caries resistances were related to bond strength with dentin and the degradation of various luting materials in acid.
4) Glass-ionomer cement showed high secondary caries resistance when the margin was finished on dentin.

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When the precoating method, which is used in inlay restorations, is applied to crown and bridge restorations, there are some problems in the direct manufacture of a temporary crown. This study investigated the effect of resin separators in building selfcuring acrylic resin (Unifast II, GC), assuming that a temporary crown is made directly on the tooth surface precoated with adhesive resin (Liner Bond II, Kuraray), and the effect of its residue on the adhesion of a luting cement (Panavia 21, Kuraray). All specimens were evaluated by the shear bond test and SEM observation of the fracture surface. Vaseline (Yakuhan), Tokuso Resin Separator (TOKUYAMA), Oxyguard (Kuraray), and Oxyguard II (Kuraray) were used, as the resin separator. The results were as follows.
(1) Between the separators used in this study, Oxyguard was the most effective separators for clinical use.
(2) The separation effect of Oxyguard dependend on polyethylene glycol, which is the main component of Oxyguard.
(3) The residue of Oxyguard on the precoated surface reduced the bond strength to Panavia 21, although this effect could be'eliminating by washing the residue off with running water for 30s.

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Depth of demineralization of human enamel surface was determined using three surface conditioning agents. Enamel surface loss by 60 s conditioning was aproxi mately 8, 0.8, and 0.2μm for 37% phosphoric acid gel, 10% citric acid with 20% CaCl₂, and Phenyl-P based self-etching primer, respectively.
Topography of wet and dried etched dentin surface was observed under a laser scanning microscope. Dentin surface etched with 37% phosphoric aced gel for 60 s showed little shrinkage in the water. However, it shrank immediately after air drying. Demineralization depth determined on the section surface was approxima tely 8μm, and shrinkage rate of demineralized dentin was approximately 50%.

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The present study discusses the efficacy of precious metal surface modification methods with heat curing resin containing 4-META, and also methods for preventing marginal leakage at the finish lines of metal dentures.
1. Tin electro-plating by KuraAce-Mini modification method and Adlloy modification with forming SnO and Ga₂O₃ on the modified surfaces were effective metal surface modifications with the heat curing resin. There were no modification effects with tin electro-plating by KuraAce, Silicoater System, Vprimer, and M-primer.
2. The marginal leaking at the finish lines can (be) prevented for finish areas of sloped type by (employing the modification methods mentioned above).
3. The stress induced by polymerization and thermal shrinkage is a large driving force to destroy the adhesion interface between the metal frame and the denture resin.

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Color matching of comoposite resin restorations placed in cavities with heavily discolored walls or a silver- colored background is extemely difficult unless an appropriate hiding material is used. The liquid type light- cured opaquer based on the Vita shade guide is useful for hiding heavily discolored areas and silver metal coloring in adhesive composite resin restorations.

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We are specialists in adhesive dentistly. We have enough knowledge about adhesion and it's technique. But Patients don't. After using adhesive technique we have to give patients right and concrete advices. The resalts of this experiment gave us right advices for patients.

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In recent years, composite resins and the respective bonding systems play the main roles in aesthetic restorative material. However, we will not be able to disregard glass ionomer cement which has the longer history as an adhesive restorative material than composite resin. Unlike composite resin, glass ionomer cement has an ability to adhere to unconditioned tooth structure in its original meaning. However, glass ionomer cement has both advantages and disadvantages as its being a cement. And the knowledge of the history and improvement of glass ionomer cement is important for the better understanding of composite resin.
Glass ionomer cement was developed as an aesthetic restorative material which adheres to tooth structure in its original meaning. Multitudinous researches of glass ionomer cement disclosed its advantages and disadvantages, so that the application of glass ionomer cement shifted from restorative material (enamel substitute) to lining and base material (dentin substitute) and luting material. Although glass ionomer cement has a lot of advantages, still it involves several disadvantages. Resin-modified glass ionomer cement was introduced to solve those disadvantages. Further improvement of resin -modified glass ionomer cement will continue to be performed. However, compared to the resin-modified glass ionomer cement, the conventional glass ionomer cement has its own superiority such as low shrinkage rate during hardening, and further improvement of the conventional glass ionomer cement is also expected.

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The history and development of lightcure glass polyalkenoate cement were described, and furthermore the setting mechanism of the cement was discussed. In addition, future improvement of the cement was claimed.

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Clearing various characteristics of resinmodified glass ionomer for filling: Fuji II LC (GC), Vitremer (3M), Photac-Fil (Espe) and Fuji II LC Improved (GC) and poly-acid composite resins for filling: Dyract (Dentsply/ DeTrey), Compoglass (Vivadent), Ionosit Fil (DMG) and Xeno (SR-5111) Sankin, marginal gap in the enamel cavity, shear bond strength to enamel and dentin, and flexural strangth following storage in water for 1 day of the products were examined. And they were compared with those of a conventional glass ionomer, Fuji II (GC) and a composite, Silux+ Scotchbond Multi-Purpose (3M).
A resin-modified glass ionomer was the shortest marginal gap width and greatest bond strength value in all materials, was the middle value of flexural strength between a mconventional glass ionomer and a composite. A poly-acid composite resin was the greatest flexural strength value in all materials, was the middle value of bond sterngth between a composite and a conventional glass ionomer and was the widest marginal gap width in all materials.

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The purpose of this study was to observe the ultrastructure of light-cured glass ionomer cements (Fuji II LC CAPSULE and Vitremer)- dentin interfaces without surface treatment (Dentin Conditioner and CA-Agent) by using light microscope and Environmental-SEM. Furthermore, the characteristics of the dentincement interface were examined by using a silver nitrate staining technique under the Cryo-SEM.
Microscopic observation of sectioned specimens revealed that some segments of light-cured glass ionomer cement were retained on the prepared dentin cavity floor without any gap formation at the inerface in almost all speciments and transparent thin layer was present on the superficial layer of the decalcified dentin. A thin cement matrix layer without unreacted core was observed at the cement-dentin interface.
It was suggested that some components of the cement matrix impregnated only the superficial layer of decalcified dentin, and insufficiently into the deep layer. Such a layer as the hybrid zone in adhesive resin restorations was not observed at the cement-dentin interface.

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The aim of this paper was to compare pulpal irritation of resin-modified glass ionomer cements with those of an adhesive composite resin and conventional glass ionomer cements based on previous reports performed independently in our department. The results of these three studies reported pulpal responses to lining cement, Liner Bond System, conventional and resin modified glass ionomer cements were compared. The comparison revealed that pulpal response to resin modified glass ionomer cements was much less than to Liner Bond System, and was comparable to conventional glass iono-mer cements.

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The objective of the paper is to discuss the fluoride release from light-cured glass ionomer cements and the fluoride effects on dentin as observed with atomic force microscopy.
The amounts of fluonide release from the light-cured glass ionomer cements Vitremer and Fuji II LC were similar or slightly higher than conventional glass ionomer cement. The amounts and rates of fluoride release from light - cured and conventional glass ionomer cements did not differ significantly. The amounts of early fluoride release from Dyract, a compomer, and Fluoro Bond, a resin bonding agent, were very low. Moreover, daily fluoride release reached a plateau earlier. It is though that rate of fluoride diffusion decreased due to an increase of the resin component.
In glass ionomer cements, acid resistant layers at the front of dentin were observed by AFM observation. It seems that the formation of these layers in light-cured glass ionomer cements require greater time than in conventional glass ionomer cement. In Fluoro Bond, the acid resistant layer was not detected. These differences were caused by the difference of fluoride availability between the materials.

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